Phase 0 scaffold: SvelteKit 5 + Drizzle + auth + storage interface

Stack matches sibling buildfor_life_* apps: SvelteKit 5 with adapter-node,
Svelte 5 runes, TypeScript, Tailwind v4 with @theme inline tokens,
PostgreSQL via Drizzle ORM, Argon2id sessions via @node-rs/argon2 and
@oslojs/crypto, EasyMDE ready for wiki/decision markdown, Sharp for
thumbnails.

Included in this commit:
- Config: package.json, svelte.config.js, vite.config.ts, tsconfig.json,
  drizzle.config.ts, .gitignore, .env.example, .gitattributes, .npmrc
- Tenancy schema: companies, users, company_users, sessions
  (10 enums pre-declared for the full domain so downstream migrations
   don't re-diff them; decision_scope widened to include asset +
   work_package per product decision)
- Auth: password hashing + SHA-256-hashed session cookies,
  session lifetime 30d with sliding renewal at T-15d,
  login + logout + session refresh in hooks
- Storage: StorageAdapter interface + LocalDiskStorage with HMAC-signed
  URLs served by /api/files, S3 drop-in with zero schema change
- UI shell: dark-mode bootstrap in app.html identical to siblings,
  sidebar (w-64, h-14 header, amber attention band pattern from repair),
  topbar with breadcrumbs, theme toggle with cross-tab sync via
  storage event, blue-600 primary, responsive drawer
- Routes: (app) authed group with auto-redirect to /login,
  (auth) login group, dashboard placeholder, error page, signed-file API
- Scripts: create-user script for bootstrapping first admin user
- Drizzle: initial migration generated (0000_init.sql)
- Shared agents and skills committed under .claude/; per-user
  permissions gitignored

Typecheck: 0 errors / 0 warnings across 555 files.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

src/routes/(app)/+layout.svelte

@@ -0,0 +1,28 @@
+<script lang="ts">
+	import type { Snippet } from 'svelte';
+	import Sidebar from '$lib/components/Sidebar.svelte';
+	import TopBar from '$lib/components/TopBar.svelte';
+	import type { LayoutData } from './$types';
+
+	let { data, children }: { data: LayoutData; children: Snippet } = $props();
+	let sidebarOpen = $state(false);
+</script>
+
+<div class="flex min-h-screen">
+	<Sidebar
+		user={data.user}
+		company={data.company}
+		companies={data.companies}
+		open={sidebarOpen}
+		onclose={() => (sidebarOpen = false)}
+	/>
+
+	<div class="flex min-w-0 flex-1 flex-col">
+		<TopBar onmenu={() => (sidebarOpen = true)} />
+		<main class="flex-1 overflow-y-auto">
+			<div class="mx-auto max-w-7xl px-4 py-6 lg:px-6">
+				{@render children()}
+			</div>
+		</main>
+	</div>
+</div>